Want to protect yourself from dementia as you age? The answer may be in your heart – literally.

That’s because the risk of heart disease in middle age can be tied to dementia later in life, according a recent study conducted by Dr. Rebecca Gottesman and others at the Johns Hopkins University School of Medicine. In fact, middle-aged people with healthy cardiovascular systems may be less likely to develop dementia in old age than those who have risk factors for heart attacks and strokes.

The findings mirror past research that links vascular risk factors like diabetes, smoking and high blood pressure to a greater probability of dementia. This study also noted that even slightly high blood pressure, or hypertension, in middle age may increase dementia risk.

“The study showed associations, but doesn’t prove that treating risk factors actually decreases risk,” Dr. Gottesman told Reuters. “That being said, we know that it is important otherwise for heart and brain health to control obesity, diabetes and high blood pressure, and to quit smoking. It is likely that controlling these over time is helpful for reducing dementia risk.”

The study explored data on 15,744 adults in Maryland, North Carolina, Mississippi and Minnesota. The average age of participants was 57, and the study ended 25 years later. By that time, approximately 1,516 people had been diagnosed with dementia, according to researchers.

It’s also interesting to note that the oldest of the participants, up to age 66, were about eight times more likely to develop dementia than those at the lower end of the age range (44 as the youngest age observed). Other factors contributed to the onset of dementia in the study, too.

– Participants with APOE (the gene associated with Alzheimer’s disease) were twice as likely to get dementia as those without it.

– Smoking in middle age was linked with 41% higher odds of dementia later in life.

– Diabetes resulted in a 77% greater risk of dementia.

– Prehypertension meant a 31% greater chance of dementia, while full-blown hypertension meant a 39% greater chance.

Vascular risk factors and disease may lead to strokes, and even speed up changes to the brain, according to medical experts. These findings, along with the advice of many doctors, stress the importance of keeping your heart health in middle age by quitting smoking or changing diet and exercise habits, for example.

“Focusing on these risk factors even before midlife provides patients an opportunity to treat and reverse these risk factors with the goal of reducing their dementia risk before it is too late,” said Hannag Gardener, a neurology researcher at the University of Miami Medical School in Florida who wasn’t involved in the study.